Naith

The Sindarin word naith literally meant 'spear-point', but over time it came to be used by the Elves for all manner of sharp or spear-like objects. Most famously, it was used to describe the approximately wedge-shaped land between the Rivers Celebrant and Anduin, where the heartlands of Lórien lay, and its capital Caras Galadhon was found.

Tolkien translates Naith into English using the word 'Gore', a very close equivalent. Just like naith, 'gore' can describe any of a wide range of narrow or pointed items, though it is now so rarely used that many readers find it almost as obscure as its Elvish equivalent.